Frequently Asked Questions (FAQ)

This is where we collect answers to the most common customer questions about the customer portal, billing, domains, shared / Managed mailcow, migrations, contracts and support.

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Customer Portal & Billing

General

Where do I log in to the customer portal?

Log in to the Servercow customer portal at cp.servercow.de/account/login using your Servercow credentials.

If an account has been shared with you, you can switch between the available accounts directly inside the portal after logging in.

I forgot my password

On the customer portal login page, use the “Reset password” function.

Please note:

• Use the email address your account is registered with.
• Also check the spam / junk folder if the email doesn't arrive.
• If no email arrives at all, contact support – ideally with your customer number or the affected domain.

I can't log in to the customer portal anymore

We migrated to a new customer portal in early February 2026. Since then, the username is exclusively the registered email address.

If your account was a shared account, it stopped working after the migration. The main account owner has to share the account with you again – the function works a bit differently in the new portal (see the How can I share an account? section).

More information: User Management.

How can I share an account?

In the User Management section of the customer portal you control who has access to your customer account: add other Servercow customers, set their permissions, and let them switch between the available accounts after logging in.

More information: User Management.

Which payment methods does Servercow support?

Currently we support:

• PayPal (one-time payments or subscription mandates)
• SEPA direct debit (mandates)
• Bank transfer
• Credit card (Visa, MasterCard, American Express – via Stripe)

Recurring payments via mandates are managed by you in the customer portal – see the Change payment method or mandate section.

Where do I find my invoices or an invoice copy?

You find your invoices in the customer portal at cp.servercow.de under Billing / Invoices. There you can see open and past invoices and download them as PDF.

If you can't find a specific invoice or don't have access, open a ticket with:

• customer number
• invoice number or period of the invoice you're looking for

Received a payment reminder, but I already paid

First check whether your payment was attributed to the correct reference / invoice number – this is the most common cause. When several invoices are open at once, attribution can be delayed.

If you've already paid, please send support the following details so the payment can be matched quickly:

• invoice number
• payment date
• amount paid
• reference used
• payment method
• for PayPal: transaction ID
• if available: proof of payment

Change payment method or mandate

You manage your payment mandates yourself in the customer portal:

1. Log in: cp.servercow.de
2. Use the dropdown menu to navigate to Mandates
3. Check the existing mandate or create a new mandate – either SEPA direct debit (account holder, IBAN, BIC), PayPal subscription or credit card
4. Optionally set a mandate as default for new invoices
5. Save / complete authorization with the payment provider

Detailed guide: Manage Mandates.

Can I extend a payment deadline?

If you can foresee that a payment will arrive late, please get in touch early – ideally before an automatic suspension or deletion can take effect.

In many cases, we can review the situation and grant a short extension. We'll need:

• customer number
• invoice number
• expected payment date

Change postal address

If your postal address changes, you can adjust it yourself in the customer portal at cp.servercow.de.

After logging in, use the dropdown menu in the top right to navigate to “Account Settings”.

Change billing address or billing email

You change billing details in the customer portal under settings.

For the billing email:

• It is used exclusively for invoices, not for other notifications.
• The primary contact address for technical communication can be different.
• Multiple accounting addresses can be entered separated by semicolons (;).
• Changes apply only to future invoices – already issued invoices are not re-sent.
• After saving, please verify the new address is stored correctly.

More information: Create an Invoice Contact.

Cancel or terminate a service

Cancellation happens via the customer portal or via a support ticket.

So the cancellation can be matched, please always include:

• customer number
• service or domain
• desired cancellation date
• whether data is still needed

Notice periods and refunds:

• A notice period of 1 month to the end of the term applies. If it's missed, the service is automatically extended by another term.
• For packages with a term longer than 1 month, there are no pro-rata refunds on early cancellation – the cancellation can however be scheduled for the end of the term.

Important

For domains, mail services and webhosting, check before cancelling whether data, mailboxes, DNS zones or backups are still needed – after cancellation, these are generally no longer retrievable.

When am I entitled to a special right of termination?

A special right of termination can apply in cases such as:

• Sudden price increases without prior notice
• Technical problems or outages that affected your business
• Data loss after incidents
• Extended unavailability of your service
• and other individual cases

If you think your case qualifies, please contact us directly. We're always committed to a satisfactory resolution for all parties.

PayPal mandates

How do PayPal mandates work?

If you pay your services using a PayPal mandate, the due amount is automatically charged to your PayPal account (or the bank account linked via PayPal) as soon as an invoice is created. You don't have to do anything, as long as the account has sufficient funds.

If there's no outstanding invoice, we don't charge anything.

You can also process one-time payments via PayPal – just select PayPal as the payment method during checkout.

Can I cancel a PayPal mandate?

Yes, at any time. In the customer portal, navigate to Mandates, select the mandate and cancel it. Guide: Manage Mandates.

SEPA direct debit

How do SEPA direct debit mandates work?

With a SEPA direct debit mandate, the invoice amount is automatically debited from your bank account as soon as an invoice is created – as long as the account has sufficient funds. Without an outstanding invoice, we don't charge anything.

Can I cancel a SEPA mandate?

Yes, at any time. Guide: Manage Mandates.

Warning

When cancelling a SEPA direct debit mandate, outstanding payments may still be collected. Make sure you have no open invoices before cancelling the mandate.

Credit card

How does credit card payment work?

Credit card payments (Visa, MasterCard, American Express) are handled by our payment provider Stripe. You can choose this method once during checkout, or store it as a credit card mandate so open invoices are charged automatically.

Guide: Manage Mandates.

Can I cancel a credit card mandate?

Yes, at any time, via the mandates section of the customer portal.

Suspension, Termination & Access

My service has been suspended. What can I do?

Suspensions usually happen because of outstanding payments or another contractual issue.

Procedure:

1. Log in to the customer portal and check open invoices.
2. Settle open invoices – reactivation usually happens after the payment arrives.
3. If you've already paid, send us proof of payment, date and amount of the payment (see the Received a payment reminder, but I already paid section).
4. If the suspension seems unjustified, open a support ticket.

As long as the service hasn't been finally deleted, it can usually be reactivated after the issue is resolved.

My service was terminated or deleted – can it be restored?

Restoration is not guaranteed and has to be reviewed case by case. It depends on why and when the service was terminated or deleted, and whether backups or exports still exist.

Please send us:

• customer or contract number
• affected domain / hostname
• which service is affected
• when you noticed the termination / deletion
• whether open invoices have been settled

If backups still exist, we'll check whether a restore or at least a data export is possible.

I can't access my service anymore / my service isn't visible in the customer portal

First check whether you're logged in to the correct customer account. With multiple companies, admin handovers or invited users it's easy to end up in an empty or wrong account.

For support to investigate, the following are helpful:

• customer number
• login email address
• affected service or hostname
• screenshot or precise description of what you see in the portal
• if available: a previous invoice or contract number

With this we can check whether the service is linked to a different customer account or whether there's a permission issue.

More information: User Management.

Domains

How do I get the Auth Code / EPP Code for a domain?

You generate the Auth Code (EPP Code) yourself in the customer portal:

1. Log in: cp.servercow.de
2. Click your customer name in the top right and choose “My Domains”
3. Open the desired domain with “View”
4. In the Transfer lock section, click “Disable transfer lock”
5. In the Authcode section, click “Generate authcode”

The Auth Code is needed to transfer the domain to another provider. The domain must be unlocked before generating it.

Before the transfer

• Outstanding invoices for the domain should be paid.
• Start the transfer well before expiration to avoid unnecessary downtime.
• A successful transfer to another registrar automatically ends the contract with Servercow.

More information: Auth Code / EPP Code.

Shared mailcow

Which DNS records do I need?

For mail reception, the MX record is mandatory:

Type	Target	Priority
MX	hosted.mailcow.de	any (e.g. 10)

For good deliverability, we additionally recommend SPF and DKIM.

Recommended SPF record:

v=spf1 include:spf.mailcow.de ~all

Important about SPF

• There may be only a single SPF record per domain. If one already exists, the existing record must be extended (no second record!).
• If you also send legitimate mail through other servers (e.g. a web server), add their IPs, e.g.: v=spf1 ip4:1.2.3.4 include:spf.mailcow.de ~all

DKIM is set up per domain. DMARC is useful but should only be set once SPF and DKIM are verifiably working.

More information: MX Record · SPF Record · DKIM + ARC · Autoconfig / Autodiscover.

IMAP / SMTP settings for my mail client

Recommended settings for the shared / hosted mailcow:

Service	Server	Port	Encryption
IMAP	hosted.mailcow.de	993	SSL/TLS (recommended)
SMTP	hosted.mailcow.de	465	SSL/TLS (recommended)
IMAP	hosted.mailcow.de	143	STARTTLS (alternative)
SMTP	hosted.mailcow.de	587	STARTTLS (alternative)

• Username: always the full email address
• Password: the mailbox password
• Authentication: Password (PLAIN) – transmission is protected by mandatory encryption

More information: Manual Mailserver configuration · Apple Mail · Thunderbird · Outlook · eM Client.

Apple Mail / iPhone stops receiving or sending

On Apple devices, the Mail app sometimes changes connection settings on its own – typically the SMTP port flips from 587 to 25 and password authentication is disabled, which makes sending fail.

Please verify in the account settings:

• SMTP port: 587 with STARTTLS or 465 with SSL/TLS
• Authentication: set to “Password”
• Username: full email address
• Server: hosted.mailcow.de
• “Automatically manage connection settings” may need to be disabled and the values corrected manually

More information: Set Up Apple Mail.

Email isn't arriving or is being rejected

Please send support the full error message / bounce mail if at all possible. Particularly helpful:

• sender address
• recipient address
• timestamp of sending
• complete bounce message with SMTP error code
• if available: mail headers / Authentication-Results

Without bounce or headers, it's often impossible to tell whether the cause is SPF, DKIM, DMARC, blacklisting, greylisting, quota or a recipient rule.

Tip

SMTP codes starting with 4xx are temporary (e.g. greylisting – retrying often helps), 5xx are permanent rejections.

My mailbox is full – and quota doesn't drop after deleting

Deleted mails often land in the trash first and continue to use storage there. The quota only drops after emptying it / syncing the client.

Procedure:

1. Delete large attachments or archive them locally
2. Empty the trash and spam / junk folder
3. Archive or delete old mails
4. In the mail client, trigger “Compact folders” or a full sync
5. Re-check the quota afterwards
6. If the display stays implausible, contact support with your mailbox address and a screenshot of the quota display
7. If storage is permanently insufficient, ask support for a quota increase or plan review

Can deleted emails be restored from a backup?

First check trash, archive and all folders in webmail / mail client – often the mails were just moved.

If the mails are really deleted, we need as much detail as possible to check a restore:

• affected mailbox
• sender or subject of the missing mail
• approximate receive timeframe
• when the deletion was noticed
• whether the mail was deleted via webmail or via a mail client

Whether a restore is possible depends on the product, the backup state and the time of deletion – we cannot guarantee it up front.

Set up forwards, aliases or group mailboxes

In the shared mailcow you can create unlimited aliases yourself as a domain admin. What's possible beyond that depends on the booked product and your permissions.

More information: Manage Aliases · Manage Domain Aliases.

How do I manage my mailboxes as a domain admin?

As a domain administrator you log in directly at hosted.mailcow.de under the “Domain Administrator” tab. Use the same credentials as for your Servercow customer account.

Important

Your customer account must be the owner of the shared mailcow. Other Servercow customers your account has been shared with cannot log in here.

There, among other things, you can:

• create, edit (name, quota in MB, password, status) and delete mailboxes
• manage aliases and domain aliases
• manage resources
• tune the spam filter

Default allowances on the shared mailcow are 20 mailboxes and 20 GB storage (may differ by plan – check the customer portal if in doubt).

More information: Log in as Domain Administrator · Manage Mailboxes · Spam Filter Settings.

Am I allowed to send newsletters or mass emails?

By default, sending is limited to a maximum of 25 external recipients per email. This limit protects the server infrastructure and the reputation of the shared mail servers with providers like Gmail, Outlook.com & co.

Sending beyond this limit constitutes mass mailing and is not permitted without prior approval.

Legally, marketing emails / newsletters are subject to strict rules (GDPR consent, documentation, imprint, unsubscribe link). A good German-language overview: Legally Compliant Email Marketing – e-recht24.de.

If your content is legally compliant, we can on request enable one or more accounts for mass mailing. Please open a support ticket describing the planned campaigns.

Caution

Unannounced or unapproved mass mailings may result in the immediate suspension of your email access – to protect all customers on the platform.

How does the spam filter learn (Spam/Ham)?

mailcow uses three methods to reliably distinguish Spam (unwanted) from Ham (wanted):

Global Bayesian filter — evaluates incoming emails by statistical probability. It automatically learns from messages whose score clearly exceeds or falls below a threshold, and additionally analyzes older already-read messages.

User-defined Bayesian filter — reacts directly when you move a mail into or out of the Junk folder. It doesn't need statistical accumulation and starts learning after just a few interactions. Important: This filter has higher priority than the global one – if they disagree, the user-defined one wins.

Fuzzy hashing — “fuzzy checksums” that detect similar emails even if parts (e.g. names) vary. A hash is only generated when a mail is classified as spam with very high probability and has been received in a similar form multiple times – simply moving a mail is not enough.

More information: Spam Filter Settings.

Which characters are allowed in mailbox addresses?

The local part of the email address (before the @) currently accepts these characters:

abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789.-_

Recommendation

Use simple, compatible combinations whenever possible, so the address works reliably across all mail clients and recipients.

If you need an additional character not on the list, open a ticket. We review whether it can be added – changes happen deliberately and carefully though, since the mail server environment is shared and stability / security take precedence.

mailcow products: Hosted/shared vs. Managed

What's the difference between Hosted/shared and Managed mailcow?

Both variants are based on Postfix and Dovecot, but they differ fundamentally in platform, resources, support and administrative depth:

• Hosted/shared mailcow – you share the platform with other customers. Administration is at domain-admin level (mailboxes, aliases, spam filter), no dedicated instance.
• Managed mailcow – a dedicated mailcow instance operated by us on top of mailcow-dockerized, with a dedicated IP, dedicated resources and the full feature set of a mailcow. We handle software updates, monitoring and operations.

If you need your own administrative control, more flexibility, dedicated resources or specific settings, a Managed mailcow (or a self-hosted mailcow) is usually the better fit.

More information: Managed mailcow · shared mailcow.

Can I book additional storage for my Managed mailcow?

Yes. The standard package includes 100 GB NVMe Ceph storage and can be extended up to 600 GB as needed. Larger expansions require a short consultation with our technicians.

For an estimate, send us a ticket with:

• hostname of the Managed mailcow
• current or desired storage amount

More information: Managed mailcow – Introduction.

Can I provision many mailboxes automatically?

On the Managed mailcow, administration is possible via the mailcow UI and the mailcow API. For larger user counts, provisioning via API from a CSV file and a script is usually the fastest path.

On the shared mailcow, standard administration is intended to be done manually via the domain admin UI.

Is there a delivery guarantee to Microsoft 365, Gmail, Yahoo?

A blanket delivery guarantee is something no serious provider can give – recipient systems, sender reputation, message content, DNS configuration and recipient-side spam filters all play a role.

We make sure to keep our mail server configuration clean and our DNS records (SPF, DKIM, DMARC) correct. For delivery problems, we need the concrete error message / bounce to investigate the specific case (see the Email isn't arriving or is being rejected section).

More information: SPF Record · DKIM + ARC.

Migration to Servercow / Managed mailcow

Do you support migrating to a Managed mailcow?

Yes, we generally support migrating to a Managed mailcow.

If you want to move from a self-hosted mailcow to a Managed mailcow at Servercow, the migration is free of charge.

If you use a different mail system, migration is not flat-rate included – scope and effort depend on the source system, the volume of data and the additional services you want. We provide an individual quote for these cases.

For a first estimate, we need:

• current provider / source system (e.g. Exchange, Microsoft 365, Google Workspace, IMAP server, existing mailcow)
• number of domains
• number of mailboxes
• rough total data volume in GB
• whether only emails or also calendars, contacts and archives should be migrated
• desired window for the switchover

With that we can estimate whether you can run the migration yourself via IMAP/tools, or whether we offer it as a service billed by effort.

What does a migration to a Managed mailcow roughly look like?

Typical sequence:

1. Ordering the desired Managed mailcow.
2. Setup of the instance and provisioning of credentials by us.
3. Creating domains, mailboxes, aliases and distribution lists in the mailcow.
4. Data import of existing emails via IMAP sync (or another migration path, depending on the source system).
5. Reduce the TTL of the current MX record so the later switchover takes effect quickly.
6. Schedule the final switchover.
7. Final DNS update (MX, SPF, DKIM, DMARC) pointing to the new environment.
8. Check / reconnect clients (Outlook, Thunderbird, smartphones …).
9. Disable the IMAP syncs – migration done.

IMAP access required

For the data sync we need IMAP access to all accounts. Two paths are common:

• an IMAP master user on the source system, or
• on the day of the switchover, all account passwords are temporarily set to a unified value and the IMAP sync runs overnight.

What we need from you up front

• A CSV export with domains, mailboxes, aliases and distribution lists – so we can provision everything automatically.
• Calendars in .ics format, ideally in a folder structure that makes clear which calendar belongs to which user.

Right after the switchover

In the first days, occasional delivery issues can occur because the IP reputation of the new environment for your domain still needs to build up. This usually settles within a few days and is normally not critical.

Is the migration included in the Managed mailcow price?

No. The Managed mailcow is primarily the mail server operated and maintained by us. A data migration from an existing system is not automatically included.

Depending on the scope, there are three options:

• you migrate the mailboxes yourself, e.g. via IMAP sync
• your IT service provider handles the migration
• we check whether we can offer the migration as a separate service billed by effort

For an estimate, we need the number of mailboxes, the data volume, and information about the source system (see the Do you support migrating to a Managed mailcow? section).

Can I test before the production migration?

Yes, a test run is generally a good idea and can be arranged with support. We prepare the test environment with a temporary domain and a temporary hostname. That way you can verify webmail, mailboxes, calendars, contacts and clients before switching the production domain via DNS.

Do Outlook, Thunderbird or smartphones need to be reconfigured after the migration?

That depends on whether server name, ports, encryption and login credentials can stay the same.

Even if an existing mail server hostname is kept, client adjustments may be necessary, e.g. for:

• IMAP / SMTP server names
• ports and encryption
• passwords
• Autodiscover / Autoconfig settings
• certificates

So plan the client switchover firmly into your migration plan.

More information: Manual Mailserver configuration · Autoconfig / Autodiscover.

Can calendars, contacts or PST files be migrated?

Emails can usually be migrated cleanly via IMAP. Calendars, contacts and PST files have to be looked at separately:

• Calendars / contacts via export and import, if the source system supports that cleanly
• PST files copied into an IMAP mailbox via Outlook
• specialized migration tools if there are lots of PST files or complex data structures

Whether and how this works in your case depends heavily on the source system. For an estimate we need details about the data source and the data volume.

Can I switch from Hosted/shared mailcow to Managed mailcow?

In principle yes, but it has to be planned as a migration – both are different product types (see the What's the difference between Hosted/shared and Managed mailcow? section).

For the switch we look at mailboxes, domains, DNS records and existing data. If you expect to grow soon, we recommend checking early whether a Managed mailcow makes sense right away – that saves a later migration.

Security & Technical

How does Servercow protect against DDoS attacks?

Unfortunately, it can happen that a host becomes the target of a (D)DoS attack.

Servercow uses a 500 Gbit/s DDoS protection via Voxility for network filtering. When a host is attacked, the packets are filtered immediately and live – the bandwidth of the servers does not degrade during that time.

Web services are additionally protected by a two-stage Web Application Firewall (WAF) that eliminates targeted attacks at the application layer.

If you are unsure or have further questions on this topic, please open a ticket – we'll respond as quickly as possible.

How are payment details stored at Servercow?

Servercow does not store the payment data used during checkout. Payments are processed through external payment providers (PayPal, Stripe, SEPA mandate providers).

Credit card and direct debit payments can also be processed via PayPal without a PayPal account at Servercow.

How do I securely transmit passwords to support?

Please never send passwords or other sensitive data unencrypted via email or ticket to us.

Even though we use extensive security measures, emails and support tickets aren't optimal for very confidential information, as they can remain accessible in transit or in conversation logs.

Instead, use our free Secrets service: https://secrets.servercow.de/.

How it works:

1. Open https://secrets.servercow.de/ in your browser.
2. Enter the password or confidential information in the text field.
3. Choose an expiration time (e.g. 1 hour, 1 day or 1 week – recommended). The entry will be automatically deleted afterwards.
4. Decide whether the content should be deleted after the first access (enabled by default) or whether you want to use your own decryption key (by default one is generated).
5. Click Encrypt message.
6. You'll get a one-time link you can safely share with us in the support ticket.

Note

Always copy the “Simple link with key” (first link), as the decryption key is already included in the URL and doesn't need to be sent separately.

Advantages:

• The link can (by default) only be opened once.
• After the chosen expiration time, the content is deleted.
• The data is not stored permanently; it only exists until the expiration time or the next restart of the service.

Contract & Support

Is there a DPA (Data Processing Agreement)?

Yes. A corresponding agreement can be downloaded via the customer portal.

After logging in, use the dropdown menu in the top right to navigate to “Account Settings” and scroll down to the GDPR section.

Where do I open a support ticket?

You open a new ticket in the customer portal at cp.servercow.de → “Your Support Requests” → choose a category → fill in the form.

For technical issues, please provide directly:

• customer number
• affected domain or email address
• exact error message
• time of the issue
• client or service in use

That way, support can help faster and more accurately.

More information: Open a New Ticket.

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Find more guides and topics in the Servercow Wiki.